JPH11264485A - Valve - Google Patents

Abstract

PROBLEM TO BE SOLVED: To surely and efficiently wash foreign matter of granule or the like sticking to a seal part or the like in a valve element and a valve seat. SOLUTION: In a valve provided with an expansion seat 6 by a sealing means of a valve element 4 and a valve seat 5, for instance, as the sealing means, by reducing a pressure to the expansion seat 6 to operate the valve element 4, a valve is opened/closed, while by expanding the expansion seat 6 so as to press it to the valve element 4, when the valve is closed, ensuring sealing performance. A gas blowing slit is provided in the vicinity of the expansion seat 6 of the valve seat 5, so as to blow out gas from the slit to a surface of the valve element 4.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an improvement in a valve used in a powder and granular material handling device such as a filter dryer, a dryer and a mixer.

[0002]

2. Description of the Related Art Conventionally, as this type of discharge valve, FIG.
As shown in FIG. 5, a hemispherical (dome-shaped) valve element 51 and a valve seat 5 are provided.
Expansion sheet 53 made of an elastic material as sealing means 2
When the valve is opened and closed, the supply pressure from the air passage 54 is reduced to loosen the expansion sheet 53, and the valve body 51 is rotated by a starter (not shown) via the shaft 55 without sliding, while the valve is closed. At this time, the supply pressure from the air passage 54 is increased to inflate the inflatable sheet 53 so that the valve element 51
There is known a valve in which the sealing property of a valve is ensured by pressing the valve.

[0003] In this device, when the valve is closed, the valve element 51 relaxes the pressure on the expansion sheet 53 and moves in the direction to close the valve. With the valve completely closed, seat 53
Press and seal. At this time, since the expansion sheet 53 is formed of an elastic material,
Is held by the elastic deformation of. When the valve body 51 is opened and closed, a gap is formed between the valve body 51 and the expansion sheet 53, so that foreign matters move along with the movement of the valve body 51 and the expansion sheet 53.
It does not move upward, so that the expansion sheet 53 does not wear.

However, in the above-mentioned conventional apparatus, if the foreign matter is large and hard, it may bite into the expansion sheet 53 and deteriorate the airtightness of the valve. Needed.

[0005] Therefore, as a discharge valve having a cleaning function, for example, Japanese Patent Application No. 334775/1995 discloses a discharge valve, which is reciprocally movable via a shaft 61 as shown in FIG. A valve provided with a valve body 62 and a valve seat 63 corresponding to the valve body 62, wherein an O-ring 64 is used as sealing means for sealing the valve body 62 and the valve seat 63, and the airtightness of the valve is maintained. When the valve body 62 closes, as the gap between the valve body 62 and the valve seat 63 decreases, air is blown into the gap from a fluid introduction hole 65 formed in the valve seat 63 in the direction of the arrow in FIG. A device that removes foreign matter attached to a part is known.

[0006]

However, in the above-mentioned conventional apparatus, since the fluid introduction hole 65 is provided only at a few places in the seal portion, the more the fluid introduction hole 65 is located, the more the fluid introduction hole 65 is blown out. The flow rate of air decreases, and the ability to clean foreign substances decreases. Therefore, it is not possible to completely remove the foreign matter adhering to a position distant from the fluid introduction hole 65, and depending on the type of the granular material, there is a problem that the seal portion must be repeatedly washed between operations. there were.

In view of the above, the present invention has been made to solve the above-mentioned conventional problems, and can reliably and efficiently clean foreign matter such as powder particles adhered to a seal portion of a valve seat and a valve body. The task is to do so.

[0008]

Means for Solving the Problems In order to solve the above-mentioned problems, a means adopted by the present invention is a valve for securing a sealing property by sealing means between a valve body and a valve seat. In addition, a slit for gas blowing is provided,
The gas is blown out from the slit to the valve body surface. Further, the slit has a configuration provided so as to form an annular groove in the valve seat.

With the above structure, when cleaning the seal portion, the gas such as nitrogen or air covers the entire seal portion.
Since the air is uniformly blown out from the slit to the surface of the valve body, foreign matters adhering to the sealing portion such as the sealing means are uniformly and reliably removed, and the airtightness of the sealing portion is improved.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment in which the valve according to the present invention is applied to a discharge valve of a device for handling powder or granular material such as a mixer will be described below with reference to the drawings.

In FIG. 1, reference numeral 1 denotes an inverted conical container of a mixer as a device for handling powders and granules, and a valve 2 for discharging the powders is attached to the lower portion of the container 1.

The valve 2 comprises a hemispherical (dome-shaped) valve element 4 rotatably mounted via a shaft 3 from a starter (not shown), and a valve seat 5 for supporting the valve element 4. The rotation of the valve body 4 opens and closes the valve 2.

Further, between the valve body 4 and the valve seat 5, FIG.
As shown in (1), an expansion sheet 6 as a sealing means is provided, and the airtightness of the valve is maintained by the expansion sheet 6. The inflatable sheet 6 is connected to an air supply source (not shown) via an air passage 7 formed in the valve seat 5, and reduces the pressure from the air supply source during opening and closing operations of the valve to reduce the inflatable sheet 6. When loosened, the valve body 4 rotates without sliding. On the other hand, when the valve is closed, the pressure from the air supply source is increased to increase the expansion sheet 6.
Is inflated and pressed against the valve body 4 to ensure the sealing of the valve.

As shown in FIG. 3, the valve seat 5 is provided with a supply path 8 for supplying air as a gas for cleaning the seal portion. The supply path 8 is connected to a gas blowing slit 9 via a ring-shaped groove 8 a for uniformly adjusting the flow of the supply gas, and is connected to a slit 9 via a supply path 8 from a gas supply source (not shown). The path of the cleaning gas for guiding the gas is configured.

As shown in FIG. 4, the slit 9 is formed in an annular shape over the entire circumference in the vicinity of the inflatable sheet 6 of the valve seat 5 at a contact portion with the valve body 4. In the direction of arrow 3, gas from the gas supply source is slit 9
Is blown out uniformly from all around. As a result, foreign matter adhering to the expansion sheet 6, the valve element 4 and the like is removed by blowing out from the slit 9. The gas blown out of the slit may be a gas such as nitrogen or air.

The slit 9 may be divided into two parts as shown in FIG. 5 and blown out from two places to the surface of the valve element 4. The slit 9 may be divided into three or more parts and blown out from a plurality of places.

In the above embodiment, the expansion sheet 6 is used as the sealing means. However, an O-ring or a gasket may be used, and if the seal between the valve body and the valve seat can be ensured, the seal of the present invention is used. It can be used as a means.

In FIG. 1, reference numeral 10 denotes an operation lever for manually opening and closing the valve, and reference numeral 11 denotes an inlet for blowing gas. Reference numeral 12 denotes a flange for fixing the valve 2 to the container 1.

Therefore, in the above embodiment, when the valve is sealed, the expansion sheet 6 is inflated and pressed against the valve body 4 to ensure the sealing property of the valve. In order to loosen the expansion sheet 6 by reducing the supply pressure, the valve element 4 rotates without sliding in the valve case. And with the valve closed,
When cleaning the seal portion, air is uniformly blown from the entire periphery of the slit 9 to the surface of the valve body 4 to remove foreign substances adhered to the seal portion such as the expansion sheet 6 and the valve body 4, thereby improving airtightness. Will be. This makes it possible to automate the cleaning work required between operations with equipment that handles powder and granular material such as a mixer, and also eliminates the need for humans to clean the seal portion, thereby improving workability. .

Incidentally, the applicant of the present invention reduced the pressure inside the container of the powder and granular material handling equipment to 35 Torr to 40 Torr,
The vacuum pump was stopped and a leak test was performed. In FIG. 8, the vertical axis indicates the pressure in the container, and the horizontal axis indicates the leak time. RUN1 indicates the blank test (change in the initial state without clogging of the granules without discharging the granules). Is shown.), And RUN2 shows a test result in a case where the washing is not performed after discharging the granular material once. As a result, in RUN2, as compared with the blank test, it can be seen that the internal pressure of the container sharply increased with the passage of time and the leak amount increased.

RUN3 and RUN4 show test results when the test is performed with the valve according to the present invention.
3 shows the test result when the washing process was performed once after discharging the granular material, and RUN4 shows the test result when the cleaning process was performed 10 times after discharging the granular material. Show. As a result, the valve according to the present invention allows the RUN3
And RUN4 are RUs that do not perform cleaning after the discharge of the granular material.
It can be seen that the internal pressure of the container rises more slowly with time as compared with N2, and the leak amount is small. That is, it was proved that the cleaning of the valve according to the present invention was effective for the sealing property of the valve.

The RUN 4 executes the test of the RUN 3 by 1
It can be seen that there is almost no difference in the amount of leakage, although this is the case where it is repeated 0 times. That is, it has been found that the valve according to the present invention does not cause a decrease in the sealing performance even if the discharge / cleaning process is repeated any number of times.

Therefore, it has been proved that the valve according to the present invention can always keep the leak amount small irrespective of the number of times of discharging and washing, and is excellent in the sealing property of the valve.

[0024]

As described above, according to the present invention, in a valve in which the sealing performance is ensured by the sealing means for the valve body and the valve seat, a slit for blowing out gas is provided near the sealing means for the valve seat. Since the gas is uniformly blown out from the entire circumference of the slit to the valve body surface, foreign matters adhering to the seal portion can be reliably and uniformly removed.
In addition, since the cleaning of the seal portion by the sealing means only needs to adjust the gas supply to the slit, manual cleaning work required between operations can be omitted. Equipment handling can be automated.

[Brief description of the drawings]

FIG. 1 is a schematic sectional view of a valve showing one embodiment of the present invention.

FIG. 2 is a sectional view of a main part showing one embodiment of a valve.

FIG. 3 is a sectional view of a main part showing one embodiment of a valve.

FIG. 4 is a sectional view taken along line AA of FIG. 1;

FIG. 5 is a view corresponding to FIG. 4 showing a modification.

FIG. 6 is a sectional view of a main part of a valve showing a conventional example.

FIG. 7 is a sectional view of a main part of a valve having a cleaning function according to a conventional example.

FIG. 8 is a diagram showing a leak test result of a valve.

[Explanation of symbols]

 2 ... valve 4 ... valve element 5 ... valve seat 6 ... expansion sheet 8a ... groove 9 ... slit

Claims (5)

[Claims] 1. A valve in which a sealing property is ensured by a sealing means between a valve body and a valve seat, wherein a slit for blowing gas is provided near the sealing means on the valve seat, and gas is supplied from the slit to the surface of the valve body. A valve characterized by being blown out. 2. The sealing means is an inflatable sheet made of an elastic material. When the valve is opened and closed, the pressure on the inflatable sheet is relaxed to operate the valve body, and when the valve is closed, the inflatable sheet is expanded. The valve according to claim 1, wherein the valve is pressed against the valve body. 3. The valve according to claim 1, wherein the slit is provided so as to form an annular groove in the valve seat. 4. The valve according to claim 1, wherein the slit is provided at at least one position of the valve seat. 5. The valve according to claim 1, wherein a groove for uniformly adjusting the flow of air is provided in a path from a supply source of the blowing gas to the slit.